Well Jonathan call me Mr. Toasty
cause in winter my shop is nice and toasty.
I fell in love and got married to a radiant heater the first time i saw it. you can see a picture below and you can see how its all mounted in the thread
http://familywoodworking.org/forums/showthread.php?t=10987&highlight=workshop+palace
Now I will tell you what made me do it.
1) I did not want to be hot and stuffy. This radiant heater heats the tools and then they radiate heat and heat the air.
2) Its natural gas or propane but i use natural gas cause i am on a main.
3) Its a fully sealed unit. It draws fresh air in from outside and exhausts outside too. Pilot light only comes on when it comes on and the pilot is in the same tube so its sealed.
4) Its insurance approved for home garages and you know how fussy those guys are.
5) It can be mounted low down even though i have mine at around 8ft
6) I can leave it on the thermostat and with my R22 insulation and tightness of my shop ( double 5/8 inch drywall) it hardly runs. But when i go in there a small touch to the thermostat and boom i am nice and toasty.
7)Cost was around $800 Canadian when i bought it. It is made in Canada down in the Niagara region but they have the same kind of thing in the USA just not sure who from.
Here is a link to my source ...nice guys.
http://www.garageheater.com/heatwave.htm
The other thing is i can stand under mine and it dont get uncomfortable.
With a sealed unit like this you have no vapor worries other than yourself suffocating from fumes in the spraying.
looking at the electik prices in USA i doubt you wanna being going there. So the radiant panels that i have seen would also be a no no to run.
Best of luck in the quest.